Research into tires the use of which reduces the energy consumption of the vehicle is now of increasing importance. One of the promising areas being explored by tire manufacturers is that of reducing the rolling resistance of the tires, notably by using low-hysteresis materials, and also reducing the mass of the tires.
It has been proposed that the mass of the tires be reduced by reducing the thicknesses of material and the specific mass of the reinforcements (through the use of textile cords) or of the compositions, or by using reinforcements that allow certain volumes of internal compositions to be reduced, for example in the bead area. Such tires are set out, for example, in U.S. Pat. No. 6,082,423 and in the documents cited in that document. Another way of reducing the mass of the tire is to reduce its overall dimensions.
All of this work has contributed towards the marketing of tires with very low rolling resistance, such as the “Energy Saver” tire marketed by the applicant company.
In spite of all the progress made over the past few years, there is still a major need to reduce the rolling resistance of tires still further while at the same time maintaining, or even improving, other performance aspects such as resistance to wear, grip or even road holding. The present invention seeks to address this need.